3.2.5.18 Processing an RDPGFX_CAPS_ADVERTISE_PDU message
The structure and fields of the RDPGFX_CAPS_ADVERTISE_PDU message are specified in section 2.2.2.18. The header field MUST be processed as specified in section 3.1.5.1. Once the RDPGFX_CAPS_ADVERTISE_PDU message has been successfully processed, the server MUST respond by sending the RDPGFX_CAPS_CONFIRM_PDU (section 2.2.2.19) message to the client, as specified in section 3.2.5.19.
If the RDPGFX_CAPS_ADVERTISE_PDU is received again during the session after the initial RDPGFX_CAPS_CONFIRM_PDU message has been sent with the version field set to RDPGFX_CAPSET_VERSION103 or later, the server MUST resend the RDPGFX_CAPS_CONFIRM_PDU (section 2.2.2.19) message to the client. The server MUST also reset the protocol to the initial state and assume that the client has disregarded all the messages sent by the server prior to RDPGFX_CAPS_CONFIRM_PDU in this channel.